1. Field of the Invention
The invention relates to a method of producing a mushroom aroma in mushroom cell masses from fermentatively cultured edible mushrooms. The cell masses are distinguished by having a high content of 1-octen-3-ol.
2. Discussion of the Background
1-Octen-3-ol is the essential aroma component which gives the edible mushrooms their typical mushroom taste. Chemical methods produce this compound as a racemate. The natural product having the intensive mushroom taste is, however, solely the levorotary enantiomer (1982 J. Agr. Food Chem., 30, 89-93).
There is a high demand in the food industry for a natural mushroom aroma, for use in preparing, for example, finished soups and sauces. Currently this demand is met chiefly by dried or ground mushrooms. Mushroom extracts and concentrates, which are also used, are prepared almost exclusively from collected forest mushrooms or from cultured mushrooms, e.g. champignons. According to Boetticher, 1974, "Technologie der Pilzverarbeitung", pp. 155-7, these products are comprised of more or less concentrated pressed juices from mushroom apothecia.
1-Octen-3-ol in cultured champignons was determined quantitatively by Wurzenberger, M., and Grosch, W., 1983, Z. Lebensm.-Unters. u. -Forsch., 16-19. According to this report, the 1-octen-3-ol is primarily present in the lamellae, and to a lesser extent in the stem. For the analytical determination of 1-octen-3-ol, the champignons were peeled, thoroughly chopped, and then extracted with pentane. The production of a mushroom aroma was not described.
U.S. Pat. No. 2,761,246 describes the fermentative culturing of edible mushrooms, with 3 stages of fermentation. At the end of the first stage care must be taken to ensure good distribution of the mycelium. Accordingly, pellets of mycelium are broken up with a microhomogenizer before the next substrate batch can be inoculated with the product. There is no production of mushroom aroma in the mushroom cell masses.
According to Klis, J. B., 1963, Food Processing, 99-101, mushroom aromas can be prepared from fermentatively cultured edible mushrooms. These products have a low content of 1-octen-3-ol, however. According to Ginterova, A., 1973, Folia Mikrobiol., 18, 277-280, this is the reason why such products have not been very successful in the marketplace, e.g. when sold as "Morel Mushroom Flavoring" in the U.S.